252 



LIGHT AND LIFE 



Reduced FMN Requirement 



A detailed analysis of the reduced FMN requirement for light 

 emission (Fig. 28) led AfcElroy and Green (13) to conclude that 

 two FMNH^ molecules were required. Subsequent studies by Totter, 

 Cormier, and Rostorfer (6) suggest that there is one tightly bound 

 flavin and one which freely dissociates. 



Aldehyde Requirement 



Similar observations with regard to the aldehyde required indicate 

 that one molecule per enzyme molecule is required for light emission. 

 The results obtained for dodecanal are shown in Fig. 29. 



Using a highly purified enzyme preparation, McElroy and Green 

 were able to demonstrate that the total light output was directly 

 dependent on the amount of aldehyde added (Fig. 30). These results 

 suggested that aldehyde utilization was essential for light emission. 



50 - 



\- 40 



X 



< 

 I- 

 o 



30 - 



20 - 







0.05 0.10 0.15 0.20 



ML DODECYL ALDEHYDE 



lig. 30. Total light versus aldehyde roiuentralioii. Kflect of varying amounts 

 of dodecyl aldehyde added to a bacterial en/ynie extract upon tlie total light 

 emitted during the reaction. 



